Functional Orthodontic Therapy for Mandibular Condyle Fracture: A Systematic Review.

The objective of this study was to compile the currently available evidence regarding the functional and morphologic outcomes of functional orthodontic therapy for mandibular condyle fracture. We performed searches in PubMed and Google Scholar as well as manually (IOK issues 2008-2019) using the keywords "trauma", "TMJ", "activator", "condylar fracture", "fracture", "mandibular condylar fracture", "occlusal splint" and "functional appliance". Screening and analysis of study eligibility were performed using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). The search strategy identified 198 studies published between 1971 and 2018, with 93 studies remaining after removing duplicate hits. Of the 93 studies, 19 were included in this study, considering the inclusion criteria. There were 12 follow-up, 4 prospective, and 3 purely retrospective studies. Some of the studies showed good functional results of mandibular condyle fracture treatment, in addition to subjective patient satisfaction. The incisal edge difference could be increased to physiological ranges of >35 mm by means of activator therapy. Partial mandibular deviations to the fractured side remained post-therapy, especially after unilateral fractures. Fractures without significant dislocation and luxation showed radiographic changes in shape, described as hypoplastic and ellipsoid, in addition to good morphologic results. One study found that collum length shortened twofold after a luxated fracture compared with fractures without significant dislocation, despite activator therapy. Straightening of the fragment occurred only in the low-dislocated fragments. Overall, children showed a higher remodeling potential than adult patients. Several studies observed an improved clinical outcome for functional therapy after mandibular condyle fracture. The outcome is essentially determined by fracture type, fracture height, and age. Further studies, especially prospective studies, are necessary to improve the evidence of functional orthodontic therapy for mandibular condyle fractures.

Histological and Histomorphometric Evaluation of Implanted Photodynamic Active Biomaterials for Periodontal Bone Regeneration in an Animal Study.

Recently, our group developed two different polymeric biomaterials with photodynamic antimicrobial surface activity for periodontal bone regeneration. The aim of the present study was to analyze the biocompatibility and osseointegration of these materials in vivo. Two biomaterials based on urethane dimethacrylate (BioM1) and tri-armed oligoester-urethane methacrylate (BioM2) that additionally contained ß-tricalcium phosphate and the photosensitizer mTHPC (meso-tetra(hydroxyphenyl)chlorin) were implanted in non-critical size bone defects in the femur (n = 16) and tibia (n = 8) of eight female domestic sheep. Bone specimens were harvested and histomorphometrically analyzed after 12 months. BioM1 degraded to a lower extent which resulted in a mean remnant square size of 17.4 mm², while 12.2 mm² was estimated for BioM2 (p = 0.007). For BioM1, a total percentage of new formed bone by 30.3% was found which was significant higher compared to BioM2 (8.4%, p < 0.001). Furthermore, BioM1 was afflicted by significant lower soft tissue formation (3.3%) as compared to BioM2 (29.5%). Additionally, a bone-to-biomaterial ratio of 81.9% was detected for BioM1, while 8.5% was recorded for BioM2. Implantation of BioM2 caused accumulation of inflammatory cells and led to fibrous encapsulation. BioM1 (photosensitizer-armed urethane dimethacrylate) showed favorable regenerative characteristics and can be recommended for further studies.

Salivary Pellicle Formed on Dental Composites Evaluated by Mass Spectrometry-An In Situ Study.

(1) Background: In the oral environment, sound enamel and dental restorative materials are immediately covered by a pellicle layer, which enables bacteria to attach. For the development of new materials with repellent surface functions, information on the formation and maturation of salivary pellicles is crucial. Therefore, the present in situ study aimed to investigate the proteomic profile of salivary pellicles formed on different dental composites. (2) Methods: Light-cured composite and bovine enamel samples (controls) were exposed to the oral cavity for 30, 90, and 120 min. All samples were subjected to optical and mechanical profilometry, as well as SEM surface evaluation. Acquired pellicles and unstimulated whole saliva samples were analyzed by SELDI-TOF-MS. The significance was determined by the generalized estimation equation and the post-hoc bonferroni adjustment. (3) Results: SEM revealed the formation of homogeneous pellicles on all test and control surfaces. Profilometry showed that composite surfaces tend to be of higher roughness compared to enamel. SELDI-TOF-MS detected up to 102 different proteins in the saliva samples and up to 46 proteins in the pellicle. Significant differences among 14 pellicle proteins were found between the composite materials and the controls. (4) Conclusions: Pellicle formation was material- and time-dependent. Proteins differed among the composites and to the control.

Clinical long-term success of contemporary nano-filled resin composites in class I and II restorations cured by LED or halogen light.

OBJECTIVES: The use of LED light-curing units (LED LCUs) for polymerising resin-based composite restorations has become widespread throughout dentistry. Unfortunately, there is a paucity of clinical longitudinal studies that evaluate the comparative efficacy of LED-based polymerisation in direct posterior composite restorations. The aim of the present study was to investigate the performance of class I and II resin composite restorations for two successful composite restorative materials cured with LED versus halogen LCUs. METHODS: One hundred restorations were placed using the nano-filled composites Grandio® or Filtek™ Supremé. The following test groups were established: LED-Grandio® n = 23 (LG), LED-Filtek™ Supremé n = 21 (LS). As controls were used: Halogen-Grandio® n = 28 (HG), Halogen-Filtek™ Supremé n = 28 (HS). All restorations were evaluated according to the clinical criteria of the CPM index (C-criteria) at baseline and after 6, 12 and 36 months. RESULTS: After 12 and 36 months, there were no significant differences between restorations polymerised with LED or halogen light. At the end of the study, 97% of the restorations showed sufficient results regardless of the employed LCU or composite. Globally, after 36 months, 56% of all restorations were assessed with code 0 (excellent) and 41% with code 1 (acceptable). In detail, excellent results (code 0) among the criteria surface quality; marginal integrity and marginal discoloration were assigned in 72, 70 and 69%. CONCLUSIONS: For the current limitations in the clinical trial design, the results showed that LED-polymerisation is appropriate to ensure clinical success of direct posterior resin composite restorations in a range of 3 years. CLINICAL SIGNIFICANCE: The choice of LCU has no significant influence on the clinical performance of posterior direct resin composite restorations within 3 years of wear.

Antibacterial photodynamic treatment of periodontopathogenic bacteria with indocyanine green and near-infrared laser light enhanced by Trolox(TM).

BACKGROUND AND OBJECTIVES: It has been shown that certain vitamins can significantly enhance the effect of photodynamic anti-tumor therapy. Unfortunately, there is no sufficient information available about the impact of those antioxidants on antimicrobial Photodynamic Therapy (aPDT). The present study is aimed at investigating the antimicrobial effect of the dye indocyanine green (ICG) in the presence of Trolox(TM) , a vitamin E analogue, upon irradiation with near-infrared (NIR) laser light (808 nm) on the gramnegative periodontopathogenic bacteria Aggregatibacter actinomycetemcomitans (A.a.), Porphyromonas gingivalis (P.g.) and Fusobacterium nucleatum (F.n.). METHODS: Bacteria solved in PBS were incubated with ICG (50-500 µg/ml) in the presence and absence of Trolox(TM) (2 mM). Irradiation was performed after 10 minutes of dark-incubation with NIR-laser-light (25-100 J/cm(2) , 810 nm). During treatment, temperature was also recorded inside the bacterial solutions. The treated suspensions were serial diluted and plated onto blood agar plates. After anaerobe cultivation for 5 days the colony-forming units (CFU/ml) were determined. RESULTS: The antibacterial effect was ICG-concentration and exposure dependent. It was found that high ICG-concentrations and light fluence rates caused bacterial reduction due to hyperthermia. Where low ICG-concentrations (<250 µg/ml) and fluence rates only induced minor regression, additional Trolox(TM) -administration significantly enhanced the photodynamic effect. While treatment of A.a. (250 µg/ml ICG, 100 J/cm(2) ) without Trolox(TM) caused no bacterial reduction, additional administration led to total eradication. In the presence of Trolox(TM) reduction to one-fifth of the original ICG-concentration (50 µg/ml) still induced total suppression of P.g. and F.n. at identical fluence (100 J/cm(2) ). Treatment with ICG, NIR-light or Trolox(TM) alone showed no remarkable bactericidal effect. Application of high ICG-concentrations (500 µg/ml) and exposure values (100 J/cm(2) ) caused peak temperatures of 64.53°C. CONCLUSIONS: The results clearly show that Trolox(TM) significantly enhanced the antibacterial effect of ICG upon irradiation with NIR-laser-light. Additional administration of Trolox(TM) may also increase the efficiency of other aPDT systems.

Photodynamic killing of Enterococcus faecalis in dentinal tubules using mTHPC incorporated in liposomes and invasomes.

OBJECTIVES: The present in vitro study investigates the antimicrobial photodynamic efficiency of the photosensitizer 5,10,15,20-tetra(m-hydroxyphenyl)chlorin (mTHPC) incorporated in liposomes (LIP) and highly flexible invasomes (INV) on the endodontopathogenic species Enterococcus faecalis in infected dental root canals. MATERIALS AND METHODS: A total of 48 root canals were prepared mechanically to file size ISO 50 and inoculated with E. faecalis for 48 h. In the test groups, the infected root canals were subjected to aPDT with either mTHPC linked to LIP or INV. The controls were either incubated with 1 % chlorohexidine gel (CHX, positive control) or root canals were irrigated with normal saline (NaCl, negative control). After treatment all canals were mechanically enlarged (ISO 50-110), and the debris of each filing process was subjected to bacterial culture analysis. RESULTS: Both mTHPC formulations showed a significant antimicrobial effect. A bacterial reduction by up to 3.6 log-steps was ascertained for INV directly at the root canal wall. aPDT using INV (ISO 60) was more effective than CHX, which caused a decrease in only 1.2 log-steps. It was found that both liposomal mTHPC formulations were capable to suppress E. faecalis inside the dentinal tubules up to 300 µm. CONCLUSIONS: The results show that mTHPC linked to LIP and INV is capable of efficiently reducing E. faecalis in dental root canals. CLINICAL RELEVANCE: As evidenced, E. faecalis is resistant to several conventional antibacterial treatment measures. In this context, photodynamic treatment with mTHPC delivered by INV is superior to temporary dressing with 1 % CHX gel applied for 24 h.

Photodynamic antimicrobial effect of safranine O on an ex vivo periodontal biofilm.

BACKGROUND AND OBJECTIVE: The increasing resistance of oral pathogens against antibiotic measures urgently requires new therapeutic strategies. In this context, antimicrobial photodynamic therapy (aPDT) may play a crucial part in the future. The aim of the present study was to compare the antibacterial efficiency of aPDT using the photosensitizer safranine O with that of chlorhexidine (0.2% CHX) on an ex vivo biofilm. METHODS: First the antibacterial activity of both measures against planktonic cultures of Streptococcus gordonii ATCC 33399, Streptococcus mutans ATCC 25175, Fusobacterium nucleatum ATCC 10953, Aggregatibacter actinomycetemcomitans ATCC 33384 and Porphyromonas gingivalis ATCC 33277 was observed. Then a patient specific ex vivo biofilm was established from plaque and saliva samples of patients (n = 19) with chronic periodontitis. The antibacterial effects of aPDT and of 0.2% CHX were determined on the ex vivo biofilms cultivated for 24 and 72 hours. After cultivation of the treated samples on blood agar (2 days) the results were quantified by counting the colony forming units (cfu/ml). RESULTS: Photodynamic treatment with safranine O showed a distinct antibacterial effect on F. nucleatum and P. gingivalis. Whereas S. gordonii was suppressed completely by aPDT, treatment with 0.2% CHX caused only a partial reduction. In the ex vivo biofilm model (24-hour biofilm), aPDT caused a significantly higher bacterial killing than treatment with 0.2% CHX. Compared to the untreated control, there was no significant difference on the 72-hour biofilm for both methods. CONCLUSIONS: The results show that oral-pathogenic species in planktonic solution can be suppressed significantly by aPDT with safranine O. Especially for bacteria in a 24-hour ex vivo biofilm, this method is more effective than treatment with 0.2% CHX. Both antibacterial treatments did not show any significant effect on the biofilm cultivated for 72 hours.

Suitability of Direct Resin Composites in Restoring Endodontically Treated Teeth (ETT).

(1) Background: The in vitro study aimed to investigate mechanical characteristics of resin composites and their suitability in direct restauration of endodontically treated teeth (ETT). (2) Methods: 38 endodontically treated premolars with occlusal access cavities were directly restored using the following resin composites and adhesives: Tetric Evo Ceram® + Syntac classic® (n = 10), Venus Diamond® + iBond Total-Etch® (n = 10), Grandio® + Solobond M® (n = 9), Estelite® Sigma Quick + Bond Force® (n = 9). After thermocycling, the elastic modulus, shear-bond-strength, fracture load (Fmax) and fracture mode distribution were evaluated. Statistical analysis: one-way ANOVA, t-test, Kruskal-Wallis test; p < 0.05. (3) Results: Grandio® showed the highest E-modulus (15,857.9 MPa) which was significant to Venus Diamond® (13,058.83 MPa), Tetric Evo Ceram® (8636.0 MPa) and Estelite® Sigma Quick (7004.58 MPa). The highest shear-bond-strength was observed for Solobond M® (17.28 MPa), followed by iBond® (16.61 MPa), Syntac classic® (16.41 MPa) and Bond Force® (8.37 MPa, p < 0.05). The highest fracture load (Fmax) was estimated for ETT restored with Venus Diamond® (1106.83 N), followed by Estelite® Sigma Quick (1030.1 N), Tetric Evo Ceram® (1029 N) and Grandio® (921 N). Fracture-mode distribution did not show any significant differences. (4) Conclusions: The observed resin composites and adhesives show reliable mechanical characteristics and seem to be suitable for direct restoration of endodontically treated teeth.

Influence of Layer Thickness and Shade on the Transmission of Light through Contemporary Resin Composites.

BACKGROUND: Material-dependent parameters have an important impact on the efficiency of light polymerization. The present in vitro study aimed to investigate the influence of the increment thickness and shade of nano- and nanohybrid resin composites on the transmission of curing light. METHODS: Three contemporary resin composites were evaluated: Tetric EvoCeram® (TEC); Venus Diamond® (VD); and Filtek Supreme XTE® (FS XTE). Light transmission (LT) was recorded in accordance with the sample thickness (0.5 to 2.7 mm) and the shade. Polymerized samples were irradiated for 10 s each using the high-power LED curing light Celalux 2 (1900 mW/cm2). LT was simultaneously recorded using the MARC Patient Simulator (MARC-PS). RESULTS: LT was strongly influenced by the composite layer thickness. For 0.5 mm-thick samples, a mean power density of 735 mW/cm2 was recorded at the bottom side. For the 2.7 mm samples, a mean power density of 107 mW/cm2 was measured. Only LT was markedly reduced in the case of darker shades. From A1 to A4, LT decreased by 39.3% for FS XTE and 50.8% for TEC. Dentin shades of FS XTE and TEC (A2, A4) showed the lowest LT. CONCLUSIONS: The thickness and shade of resin composite increments strongly influences the transmission of curing light. More precise information about these parameters should be included in the manufacture manual.

Coaxial electrospun nanofibers as drug delivery system for local treatment of periodontitis.

OBJECTIVES: The aim of the present study was to prepare resorbable polylactide fibers for periodontitis treatment using coaxial electrospinning to optimize the release of metronidazole (MNA) by reducing the initial burst effect. METHODS: Poly(L-lactide-co-D,L-lactide) (PLA) fibers mats with different distributions of metronidazole (MNA) were manufactured by coaxial electrospinning (COAX). By COAX spinning the central core of the fiber was enriched with 40% MNA (m/m), while the sheath of the fiber consisted of PLA only (test group). In contrast, fibers of the control group were prepared by conventional electrospinning with the same amount of MNA but with a homogenous drug distribution (HDD - homogenously distributed drug). The release of MNA was determined by analyzing aliquots from the fiber mats using UV-VIS spectroscopy. Agar diffusion tests were carried out to determine the antibacterial effect on periodontopathogenic bacteria. Biocompatibility was tested in direct contact to human gingival fibroblasts (HGF) for two days. RESULTS: The COAX mats showed a retarded drug release compared to the conventional HDD fibers. After 24 h, 64% of total MNA was released cumulatively from the COAX fibers while 90% of the MNA was released from the HDD fibers (controls). The antibacterial effect of COAX fibers was significantly higher after 24 h compared to the HDD fibers. Cell cultivation revealed significant higher numbers of vital cells among the COAX mats. SIGNIFICANCE: COAX fibers showed improved sustained MNA release compared to conventional fibers and can be seen as potential drug delivery systems in local periodontitis treatment.

Photodynamic Suppression of Enterococcus Faecalis in Infected Root Canals with Indocyanine Green, TroloxTM and Near-Infrared Light.

Recently, our group showed that additional supplementation of Trolox™ (vitamin E analogue) can significantly enhance the antimicrobial photodynamic effect of the photosensitizer Indocyanine green (ICG). Up to now, the combined effect has not yet been investigated on Enterococcus faecalis in dental root canals. In the present in vitro study, eighty human root canals were inoculated with E. faecalis and subsequently subjected to antimicrobial Photodynamic Therapy (aPDT) using ICG (250, 500, 1000 µg/mL) and near-infrared laser light (NIR, 808 nm, 100 Jcm-2). Trolox™ at concentrations of 6 mM was additionally applied. As a positive control, irrigation with 3% NaOCl was used. After aPDT, root canals were manually enlarged and the collected dentin debris was subjected to microbial culture analysis. Bacterial invasion into the dentinal tubules was verified for a distance of 300 µm. aPDT caused significant suppression of E. faecalis up to a maximum of 2.9 log counts (ICG 250 µg/mL). Additional application of TroloxTM resulted in increased antibacterial activity for aPDT with ICG 500 µg/mL. The efficiency of aPDT was comparable to NaOCl-irrigation inside the dentinal tubules. In conclusion, ICG significantly suppressed E. faecalis. Additional application of TroloxTM showed only minor enhancement. Future studies should also address the effects of TroloxTM on other photodynamic systems.

Clinical effects of laser-based cavity preparation on class V resin-composite fillings.

The aim of the present clinically controlled two-year study was to investigate the influence of laser-based cavity preparation on the long-term performance of Class V resin-composite fillings. Class V non-carious lesions (n = 75) were randomly assigned to two test and one control group. Cavities in both test groups were prepared using an Er,Cr:YSGG laser (Waterlase MD, Biolase, Irvine, California, USA). The device was operated at 3 W (150 mJ, 30 J/cm2), 50% water, 60% air, 30 Hz in H mode. Subsequently, laser-prepared tooth surfaces in test group I (n = 21) were additionally conditioned by acid etching (etch-and-rinse). Laser-prepared cavities of test group II (n = 21) received no additional acid conditioning. After application of an adhesive, all cavities were restored using the resin-composite Venus®. For cavities in the control group (n = 33) conventional diamond burs were used for preparation which was followed by an etch-and-rinse step, too. The fillings were evaluated immediately (baseline) and after 6, 12 and 24 months of wear according to the C-criteria of the USPHS-compatible CPM-index. The results showed that after 24 month of wear, laser-preparation was associated with fillings of high clinical acceptability. Compared to conventional bur-based treatment, laser-based cavity preparation resulted in fillings with high marginal integrity and superior marginal ledge configurations (p = 0.003). Furthermore, laser-preparation combined with additional acid-conditioning (test group I) resulted in fillings with the best marginal integrity and the lowest number in marginal discoloration, especially at the enamel-composite margins (p = 0.044). In addition, total loss of fillings was also less frequently observed in both laser groups as compared to the control. The results clearly demonstrate that laser-based cavity preparation will benefit the clinical long-time performance of Class V resin-composite fillings. Furthermore, additional acid-conditioning after laser preparation is of advantage.

Remineralization of Artificially Demineralized Human Enamel and Dentin Samples by Zinc-Carbonate Hydroxyapatite Nanocrystals.

(1) Background: Decalcified enamel and dentin surfaces can be regenerated with non-fluoride-containing biomimetic systems. This study aimed to investigate the effect of a zinc carbonate-hydroxyapatite-containing dentifrice on artificially demineralized enamel and dentin surfaces. (2) Methods: Human enamel and dentin discs were prepared and subjected to surface demineralization with 30% orthophosphoric acid for 60 s. Subsequently, in the test group (n = 20), the discs were treated three times a day for 3 min with a zinc carbonate-hydroxyapatite-containing toothpaste (biorepair®). Afterwards, all samples were gently rinsed with PBS (5 s) and stored in artificial saliva until next use. Samples from the control group (n = 20) received no dentifrice-treatment and were stored in artificial saliva, exclusively. After 15 days of daily treatment, specimens were subjected to Raman spectroscopy, energy-dispersive X-ray micro-analysis (EDX), white-light interferometry, and profilometry. (3) Results: Raman spectroscopy and white-light interferometry revealed no significant differences compared to the untreated controls. EDX analysis showed calcium phosphate and silicon dioxide precipitations on treated dentin samples. In addition, treated dentin surfaces showed significant reduced roughness values. (4) Conclusions: Treatment with biorepair® did not affect enamel surfaces as proposed. Minor mineral precipitation and a reduction in surface roughness were detected among dentin surfaces only.

Photodynamic suppression of Enterococcus faecalis using the photosensitizer mTHPC.

BACKGROUND AND OBJECTIVES: Enterococcus faecalis is frequently found in persistent endodontic infections. In this context, the antimicrobial photodynamic therapy (aPDT) could become a modern alternative to existing antibacterial treatment approaches. The aim of this study was to investigate the effect of aPDT on E. faecalis using the photosensitizer (PS) 5,10,15,20-tetra(m-hydroxyphenyl)chlorin (mTHPC) enriched in liposomes. MATERIALS AND METHODS: Enterococcus faecalis was cultivated in Schaedler submerged culture for 24 hours, then isolated and adjusted in PBS to 10(8) cells/ml. The bacterial suspension was pipetted into a black microtitration plate and incubated for 15 minutes in the dark with mTHPC in various concentrations (10, 30, and 50 µM). The photosensitized suspensions were subjected to laser light (652 nm) at a light fluence of 100 J cm(-2) (test group A). In addition, the suspension sensitized with 50 µM mTHPC was irradiated with 25, 50, and 75 J cm(-2) (test group B). The following controls were used: non-irradiated bacterial suspension in the absence of mTHPC (C); irradiated bacterial suspension in the absence of mTHPC (D); non-irradiated bacterial suspension incubated with mTHPC (E). Dilution series (10(0)-10(-6)) were made of all groups and applied on Schaedler agar. After anerobic cultivation (4 days), the colony-forming units (CFU/ml) were determined. RESULTS: Enterococcus faecalis was suppressed completely after incubation with 50 µM mTHPC and illumination with 100 J cm(-2). Photodynamic treatment with 10 and 30 µM mTHPC caused reduction in CFU by 5.8 and 6.7 log-units. The application of an energy fluence <100 J cm(-2) resulted in a decline of antibacterial efficiency. Irradiation of the non-photosensitized solution showed no suppressing impact. Incubation of the PS without additional irradiation caused a maximal reduction in CFU by 1.5 log-units. CONCLUSION: The results show that aPDT using the PS mTHPC incorporated in liposomes could be a new approach to adjuvant treatment of endodontic infections with E. faecalis.

Effectiveness of Casein Phosphopeptide-Amorphous Calcium Phosphate (CPP-ACP) Compared to Fluoride Products in an In-Vitro Demineralization Model.

The goal of this study was to evaluate the effectiveness of the toothpaste Tooth Mousse compared to conventional fluoride-based versions in the prevention of enamel and dentin demineralization. Human enamel and dentin samples (n = 120 each) were exposed to artificial demineralization at pH 4.92. During the demineralization process, the samples in the test groups were periodically treated with Tooth Mousse (TM) containing casein-phosphopeptide -amorphous-calcium-phosphate (CPP-ACP) and Tooth Mousse Plus (TMP) containing amorphous-calcium-fluoride-phosphate (CPP-ACPF) to evaluate their protective properties. Fluoride toothpastes containing 1400 ppm amine fluoride (AmF) and 1450 ppm sodium fluoride (NaF) were applied in the positive control groups. Treatment with distilled water (group C-W) or demineralization without treatment (group C-D) served as negative controls. After the demineralization and treatment process, all samples were cut longitudinally and lesion depths were determined at six locations using polarized light microscopy. In TM/TMP groups (enamel: 80/86 µm, dentin: 153/156 µm) lesion depths were significantly smaller compared to the negative control groups C-W/C-D (enamel: 99/111 µm, dentin: 163/166 µm). However, TM and TMP compared to the positive controls AmF/NaF (enamel: 58/63 µm, dentin: 87/109 µm) showed higher lesion depths. The application of TM/TMP (89%/78%) during demineralization led to a reduced number of severe lesions compared to the negative controls C-W/C-D (100%/95%). In this study we demonstrate that Tooth Mousse is less effective regarding prevention of enamel and dentin demineralization compared to fluoride containing toothpastes.

Antibacterial Effect of Endodontic Disinfections on Enterococcus Faecalis in Dental Root Canals-An In-Vitro Model Study.

Enterococcus faecalis (E. faecalis) is rather unsusceptible to many root canal disinfections which often cause a therapeutic problem. Therefore, the present in vitro study observed the efficiency of different endodontic antiseptics in their capability to suppress E. faecalis, especially inside dentinal tubules. Prior to any testing, root canals of extracted third human molars were inoculated with E. faecalis for 48 h. Antiseptic dressings with chloramine-T or calcium hydroxide (CaOH) for 24 h or irrigations with 1.3% sodium hypochlorite (NaOCl) were applied with n = 10 in each group. As control irrigation with normal saline was used. All treated canals were manually enlarged from size ISO 50 to 110 and the ablated dentin debris was subjected to microbial culture analysis. Bacterial colonization of the dentinal tubules up to 300 µm was verified by scanning electron microscopy and histological sample preparation. Application of crystalline chloramine-T caused total bacterial suppression inside the dentinal tubules. Dressings with CaOH showed only minor effects. Irrigation with NaOCl caused total eradication of bacteria adhering to the root canal walls, but also failed to completely suppress E. faecalis inside the dentinal tubules. The study showed that chloramine-T is of strong antiseptic activity and also efficient in suppressing E. faecalis inside dentinal tubules.

Antimicrobial Effect of Natural Berry Juices on Common Oral Pathogenic Bacteria.

(1) Background: Antimicrobial agents such as chlorhexidine (CHX) are commonly used in oral plaque control. However, sometimes those agents lack antimicrobial efficiency or cause undesired side effects. To identify alternative anti-infective agents, the present study investigated the antibacterial activity of all-fruit juices derived from blackcurrant, redcurrant, cranberry and raspberry on common oral pathogenic gram-positive and gram-negative bacteria (Streptococcus mutans, Streptococcus gordonii, Streptococcus sobrinus, Actinomyces naeslundii, Fusobacterium nucleatum, Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Enterococcus faecalis). (2) Methods: Antibacterial efficiency was evaluated by agar diffusion assay and in direct contact with bacteria in planktonic culture. Furthermore, cytotoxicity on human gingival fibroblasts was determined. (3) Results: Blackcurrant juice was most efficient at suppressing bacteria; followed by the activity of redcurrant and cranberry juice. Raspberry juice only suppressed P. gingivalis significantly. Only high-concentrated blackcurrant juice showed minimal cytotoxic effects which were significantly less compared to the action of CHX. (4) Conclusion: Extracts from natural berry juices might be used for safe and efficient suppression of oral pathogenic bacterial species.

Effect of biomimetic mineralization on enamel and dentin: A Raman and EDX analysis.

OBJECTIVE: To investigate the effect of an experimental biomimetic mineralization kit (BIMIN) on the chemical composition and crystallinity of caries-free enamel and dentin samples in vitro. METHODS: Enamel and dentin samples from 20 human teeth (10 for enamel; 10 for dentin) were divided into a control group without treatment and test samples with BIMIN treatment. Quantitative analysis of tissue penetration of fluoride, phosphate, and calcium was performed using energy-dispersive X-ray spectroscopy (EDX). Mineralization depth was measured by Raman spectroscopy probing the symmetric valence vibration near 960cm-1 as a marker for crystallinity. EDX data was statistically analyzed using a paired t-test and Raman data was analyzed using the Student's t-test. RESULTS: EDX analysis demonstrated a penetration depth of fluoride of 4.10±3.32µm in enamel and 4.31±2.67µm in dentin. Calcium infiltrated into enamel 2.65±0.64µm and into dentin 5.58±1.63µm, while the penetration depths for phosphate were 4.83±2.81µm for enamel and 6.75±3.25µm for dentin. Further, up to 25µm of a newly mineralized enamel-like layer was observed on the surface of the samples. Raman concentration curves demonstrated an increased degree of mineralization up to 5-10µm into the dentin and enamel samples. SIGNIFICANCE: Biomimetic mineralization of enamel and dentin samples resulted in an increase of mineralization and a penetration of fluoride into enamel and dentin.

Bactericidal and Biocompatible Properties of Plasma Chemical Oxidized Titanium (TiOB®) with Antimicrobial Surface Functionalization.

Coating of plasma chemical oxidized titanium (TiOB®) with gentamicin-tannic acid (TiOB® gta) has proven to be efficient in preventing bacterial colonization of implants. However, in times of increasing antibiotic resistance, the development of alternative antimicrobial functionalization strategies is of major interest. Therefore, the aim of the present study is to evaluate the antibacterial and biocompatible properties of TiOB® functionalized with silver nanoparticles (TiOB® SiOx Ag) and ionic zinc (TiOB® Zn). Antibacterial efficiency was determined by agar diffusion and proliferation test on Staphylocuccus aureus. Cytocompatibility was analyzed by direct cultivation of MC3T3-E1 cells on top of the functionalized surfaces for 2 and 4 d. All functionalized surfaces showed significant bactericidal effects expressed by extended lag phases (TiOB® gta for 5 h, TiOB® SiOx Ag for 8 h, TiOB® Zn for 10 h). While TiOB® gta (positive control) and TiOB® Zn remained bactericidal for 48 h, TiOB® SiOx Ag was active for only 4 h. After direct cultivation for 4 d, viable MC3T3-E1 cells were found on all surfaces tested with the highest biocompatibility recorded for TiOB® SiOx Ag. The present study revealed that functionalization of TiOB® with ionic zinc shows bactericidal properties that are comparable to those of a gentamicin-containing coating.

Microsomal hydroxylation and glucuronidation of [6]-gingerol.

[6]-Gingerol is the major pungent principle of ginger and frequently is ingested with various condiments and nutritional supplements. We report here that incubation of [6]-gingerol with NADPH-fortified rat hepatic microsomes gave rise to eight metabolites, which were tentatively identified by GC-MS analysis as two products of aromatic hydroxylation as well as the diastereomers of two aliphatic hydroxylation products and the diastereomers of [6]-gingerdiol. Hepatic microsomes from rats and humans fortified with UDPGA glucuronidated [6]-gingerol predominantly at the phenolic hydroxyl group, but small amounts of a second monoglucuronide involving the aliphatic hydroxyl group were also identified by LC-MS/MS analysis. Human intestinal microsomes formed the phenolic glucuronide only. Supersomes containing human UGT1A1 and 1A3 exclusively generated the phenolic glucuronide, albeit with very low activities, whereas UGT1A9 catalyzed the specific formation of the alcoholic glucuronide and UGT2B7 the predominant formation of the phenolic glucuronide with high activities. Our study indicates a rather complex metabolism of [6]-gingerol, which should be taken into consideration for the multiple biological activities of this compound.